I saw this on your front page:

Some people are unable to save a .ppd project into the app root folder. To avoid this just save the project to another folder.

Just FYI, I was unable to save in a different folder, too. If this continues being a challenge (saving to a file in GameMaker is surprisingly difficult), consider trying to use an INI file instead. It's not as contained, but GameMaker has good support for INI.

This is actually the first report I get about not being able to save into a different folder. I'll take a look at it. Changing the format to INI it's on my mind, it's still sandboxed and, as you said, surprisingly difficult to save a file outside the GM's temporary folder.

Thanks for the report.

Hi! This program is amazing, but I have not been able to save either.